1. Field of the Invention
The present invention relates to an apparatus and method for treating contaminated soil, particuarly soil contaminated with hydrocarbons, and particularly relates to such a portable apparatus and method for removing and reclaiming volatile hydrocarbon products from contaminated soil in an environmentally compatible method.
2. Description of the Prior Art
During the oil boom of the last few decades, oil well drilling sites were not noted for their environmental friendliness. The primary concern was to remove the oil and gas (hydrocarbon products) from the ground, with little thought to environmental issues. As a result, there are numerous sites wherein the soil is contaminated with hydrocarbon byproducts, oil sludge, etc.
Environmental awareness having been brought to the forefront, it is now commonly appreciated that it is necessary to go back and clean these previously contaminated areas. Various systems and methods have been attempted to remediate the contaminated soil, i.e., remove the hydrocarbon waste materials therefrom, leaving environmentally acceptable soil. One of these devices is shown in U.S. Pat. No. 5,193,291, which shows a conventional "baghouse" system wherein the contaminated soil is heated directly by a gas furnace flame, the heated soil thereafter being discharged into the baghouse for subsequent separation and discharge.
U.S. Pat. No. 5,188,041 discloses a soil remediation process comprising passing non-oxidizing heated gases over the contaminated soil at a flow rate and temperature to prevent surface drying of the contaminated soil. This system is specifically a low-temperature system, and therefore is incapable of effectively remediating most hydrocarbon contaminated soils. U.S. Pat. No. 5,272,833 shows a similar apparatus and process for remediating contaminated soil. This system is also a baghouse-type system, similar to that of U.S. Pat. No. 5,193,291.
U.S. Pat. No. 5,004,486 discloses a gas cleaning system that directs the exhaust gas from the combustion chamber through a heat exchanger for cooling the gas, and into a bubbling dust separator submerged under water in order to discharge the gas directly into the water for the prevention of air pollution.
U.S. Pat. No. 5,273,355 discloses a rotary drum mechanism for incinerating soil and mixing the soil with heated and dried stone aggregate for the production of asphalt paving. The gas products of combustion from the incinerator are directed into the rotary drum to be further combusted prior to direct discharge into the atmosphere.
U.S. Pat. No. 5,302,118 discloses a soil remediation system comprising a rotary drum having a burner flame directed into one end of the drum, as in U.S. Pat. No. 5,193,291. In addition, as in the '291 Patent, the '118 Patent includes the baghouse-type collection mechanism for collecting dust to prevent its release into the atmosphere.